In many irrigation systems, the need arises to facilitate supplemental watering of the irrigated areas as well as access to water under pressure for washing of pavement areas such as sidewalks or the like. To facilitate this need to provide supplemental watering and washing capability, irrigation systems frequently provide additional vertical supply pipes rising upwardly from the irrigation main line systems together with vertically extending valves known in the art as "quick coupling valves". Such valves are intended to provide access to water under pressure for coupling a hose fitting or the like to the water supply using a convenient key which functions as a valve actuater and as a coupling pipe to receive and secure the hose fitting. In most instances, the valve is positioned such that a key receptacle extends above the surrounding soil surface. A pivotally secured valve cover is secured to the key receptacle and provides protective closure of the key receptacle interior components and valve apparatus.
While the structures of such quick coupling valves and their installation is subject to some variation, all generally comprise the same basic operative components. FIG. 1 sets forth a perspective view of a typical prior art quick coupling valve and related installation and components. Thus, with reference to FIG. 1, a quick coupling valve 10 is shown positioned within a surrounding soil pack 19 in a typical installation. Valve 10 includes a valve body supporting a generally cylindrical key receptacle 15 extending upwardly from valve body 11 and defining a key passage 18 extending downwardly. Valve body 11 further includes a threaded attachment nut 14 which is threadably received upon a plurality of threads 13 formed on a vertically extending supply pipe 12. Supply pipe 12 is coupled to a convenient portion of the irrigation feed system having water under pressure (not shown). Thus, water under pressure is present within supply pipe 12 and restrained by the operative mechanism of valve 10. In further accordance with conventional fabrication techniques, a valve key 20 includes an elongated generally cylindrical hollow key body 21 having an end portion received within passage 18 and coupled to the operative mechanism of valve 10. Valve key 20 further includes a horizontally extending handle 22 and a plurality of threads 23 at the upper end thereof. A conventional threaded elbow fitting 24 is received upon threads 23 and further receives a hose fitting 25 in a conventional attachment. Key receptacle 15 further supports a pivotally attached valve cover 16 having a pivot pin 17 passing therethrough. In the absence of valve key 20, valve cover 16 pivots downwardly upon the upper end of key receptacle 15 providing a protective closure of receptacle 15.
While not seen in FIG. 1, in accordance with conventional fabrication techniques, the valve mechanism within valve 10 includes a spirally configured keyway. Correspondingly, the lower end of valve key 20 includes a hollow tube having a side lug cast on the side portion thereof which extends into the spirally configured keyway of the valve. Once the key is inserted into the valve body and rotated through a distance between ninety and one hundred eighty degrees, its lower end portion is forced against a spring loaded poppet valve in the valve body. Once the poppet is driven away from its seat, a flow of water then travels upwardly through the valve body, key receptacle and hollow key body 21 to pass through elbow 24 and hose fitting 25. The closure of valve 10 is carried forward in a basically reverse operation in which handle 22 is pivoted counterclockwise causing valve key 20 to move upwardly due to the cooperation of the key lug and spirally configured keyway in the valve body. The upward movement and removal of valve key 20 allows the spring loaded poppet to return to its closed position terminating water flow.
While such quick coupling valves are important to the full use and operation of certain irrigation systems, their operation in the above-described manner produces substantial torquing of the coupling between supply pipe 12 and valve body 11. This torquing in both directions indicated in FIG. 1 by arrows 28 tends to loosen and wear the threaded coupling between the valve body and supply pipe. Since the entire system pressure is applied against the valve in the closed position, the wearing of the threading coupling undermines the system integrity and may eventually lead to complete separation of the valve from the supply pipe. The packed soil about the quick coupling valve does little if anything to resist the torsional forces applied to the valve.
In response to the potential problems associated with failure of the valve to supply pipe attachment, practitioners in the art have typically provided torque resisting anchors secured to the valve body. FIG. 1 shows a typical torque resisting anchor of the prior art construction installed upon valve 10. Thus, an elongated member usually formed of an angle iron segment 26 defines a pair of apertures on each side of valve body 11 which in turn receive a U-shaped bolt 27. While not seen in FIG. 1, it will be understood that the end portions of U-bolt 27 extending through angle iron 26 are threaded and receive conventional threaded fasteners and locking nuts. The objective is to tighten U-bolt 27 against angle iron 26 captivating and securing valve body 11. Angle iron 26 is intended to be supported by soil pack 19 and resist torsional forces upon valve 10.
While the prior art attempts to provide torque resisting anchors for such quick coupling valve have, in some instances provided improvement, they have often proven themselves to be ineffective or marginally effective. For example, the rising and lowering of soil pack 19 and valve 10 due to normal expansion and contraction of irrigation system components and pressure within the system as well as the swelling and compacting of the soil pack often induce slippage between U-bolt 27 and valve body 11. This slippage eventually allows U-bolt 27 to slip away from valve body 11 rendering the valve anchor mechanism virtually ineffective. In addition, such U-shaped bolts as U-bolt 27 provide a relatively small gripping force against torque over a long term in that they have a tendency to wear if subjected to torque or stretch and loosen.
There arises therefore a need in the art for a more effective torque resisting anchor for irrigation valves.